No expert on the F2. I doubt you would gain very much. I would expect you would have to rejet as the F2 head is a bit free-er flowing with the larger valves. Only advantage I can think of is don't the F2 carbs have accellerator pumps? this could, in theory, give better 'pick up' ( or even make it worse by dumping a load of fuel in the F1 head can't cope with? ) personally, once you had got it all correct I doubt you would notice any difference as I would bet the F2 carbs ran leaner ( for emmisions purposes ) and so needed the pumps.
As I say, am no expert on these specific carbs, just my opinion